Recently, there has been a growing interest for those in the health fields for developing biosensors, molecular libraries, Lab-on-a-Chip (LOC), and other biological electronic and bio-MEMS based devices. Lab-on-a-chip (LOC) refers to devices that integrate multiple laboratory functions on a single chip. Such chips are capable of managing extremely small volumes of fluid, for example, in the range of pico-liters or less. LOC generally involves the scaling of single or multiple lab processes down to chip-format to perform chemical analysis. Many uses are possible for LOC devices such as immunoassays to detect bacteria, viruses and cancers based on antigen-antibody reactions; dielectrophoresis for detecting cancer cells and bacteria, or blood sample analysis.
Controlled fluid delivery to a semiconductor die is of utmost importance for such biological sensor applications. Generally this delivery involves creating physical channels or trenches in a substrate in which the fluid may travel to reach the die where chemical analysis may be performed.